Some questions I have before my IFR checkride...

[taseal]

I'm going over some airline interviews to see if I can catch any IFR stuff that I might have missed (I think its a good way to find out some questions people ask) and I came across this. but I don't quite get it:

• Decode a METAR and TAF
  • Can we depart (referencing a 10-9 airport information page)?
  • How do you know?
  • What if RVR is reported as 6-6-6, can we depart?
  • What if it drops to 5-6-6?
  • What if an RVR value isn’t reported put the others are 6 and 6, can we depart? How do you know?
  • Convert Celsius to Fahrenheit
  • If visibility is ½ miles and RVR is 1200 can we depart?
    

whats with the 6-6-6, 5-6-6 and what isa 10-9 airport info page? something out of AIM? lol

if there isa RVR reported, 121 guys need a certain RVR (or vis if no RVR present) to TO right? this doesn't apply to 91 however. we can depart 0 vis if we wanted.

I'm also a bit confused about the diff between RVV and RVR. what is the diff?

lets say the RVR is 1800 and vis 1/4. the mins for that app is higher (3600 and 3/4 lets say) as a part 91 pilot, can I still shoot that app? (afaik I can still shoot the app as a part 91 pilot, because both are not reported distances from the air. However if tower says that the visual range from the tower is 2000, I can no longer shoot that app correct?)

I feel ready for this end of course, but I get nervous near the end and I start questioning myself. especially when they do the 'are you sure' trick. hopefully everything will go fine. I'll put up some questions as I think of them and can't figure it out.

thx in advance guys!


ps: another one what is diff between MCA and MOCA.

MCA = min crossing alt (yo must be at this alt by the time you cross that fix, but what are the obst clearance altitudes?)

MOCA = min obst clearance alt which provides 1,000 non mts, 2,000 mts clearance, plus reliable nav aid reception upto 22 miles from the navaid)

oh, 1 more.... grid MORA. what area does it cover? like a 50 mile radius? I know the MORA is 10NM from eachside of the airway. butnot sure about grid MORA. I know they turn red after 14,500 though.

[taseal]

what defines a mountainous area?

[ScottG]

Originally Posted by taseal

what defines a mountainous area?

I got a few answers, just after skimming....

You are right that 91 ops need "0" RVR to TO and I believe it depends on A\C for anything else....1 engine, 2 engine and so on.

MCA is the minimum altitude to cross a fix usually due to MEA on other side. MOCA is minimum for obstacle clearance ONLY with the exception of acceptable nav coverage within 24ish N.M. of a facility. As I understand it you will likely never use this but say you lose com and need to descend, you are safe at the MOCA but nav might be unavailable. I THINK it has its place for ATC as well...

Mountainous terrain is defined in a certain chart found in the AIM, don't know the name but pretty much all of the western US and the Appalachian Mtns area are considered "mountainous".

[germb747]

You're preparing for the FAA Instrument Rating right? Get ahold of the "Oral Exam Guide" at the local pilot shop and read through it a few times. Also, King Schools puts out good videos that show a mock oral/practical. Those two things covered everything I was asked on my IFR oral, don't worry about any of the Part 121 crap. You can take off 0-0 if you want to. You can shoot an approach 0-0 if you want to as well, for that matter.

It's been 10 years since I took my initial instrument training, but definitely know stuff like when is an alternate required for Part 91; what qualifies as an alternate. Know all the Part 91 IFR regs cold, equipment required for IFR, etc. Read up on what you need to continue below minimums and land, (i.e. what constitutes having the runway environment in sight, what can you do if you only have the approach lights in sight (go 100ft below mins), what visibility do you need, be in a safe position to make a normal landing, etc.)

Good luck!

[mikecweb]

Who you taking it with?

[chrisdahut1]

taseal,

Kudos on trying to further your instrument knowledge, but what you're doing might be a tad counter productive. At your level, you only need to be concerned about Part 91 regulations. Don't start studying the additional (and often confusing) layer of regulations that is part 121 until you are at the very least finished with the IR. All the questions you asked have answers that at this point in time are of no concern to you, and by trying to learn and memorize the answers you may start getting a little overwhelmed!

Here's some answers you might find useful:

"whats with the 6-6-6, 5-6-6 and what is a 10-9 airport info page? something out of AIM? lol"

-6-6-6 (or any combination of numbers used in that context) refers to RVR value. Runways approved for low visibility takeoffs will typically have 3 RVR systems per runway- referred to as touchdown, mid and rollout RVR. Each number corresponds to the minimum visibility each RVR must report (in hundreds of feet) in order to be legal to depart under 121. For example, if someone says "the RVRs are 5-6-3" they mean "The Touchdown RVR is reporting 500 ft, the Mid RVR is reporting 600 ft and the roll out RVR is reporting 300 feet". You'll hear the numbers "6-6-6" get quoted often as this is typically the lowest value that any airline or runway will be approved for.

10-9 refers to the number on the top of Jeppesen airport diagrams (that also contain minimum take off visibility data for each runway).

"I'm also a bit confused about the diff between RVV and RVR. what is the diff?"

-RVV stands for "Runway Visibility Value" and RVR stands for "Runway Visual Range". RVV is RVR's less precise cousin...it'll give you a visibility value for the runway much like the tower or a METAR will give prevailing visibility in SM rather then feet (eg - 1/4SM visibility).


"lets say the RVR is 1800 and vis 1/4. the mins for that app is higher (3600 and 3/4 lets say) as a part 91 pilot, can I still shoot that app? (afaik I can still shoot the app as a part 91 pilot, because both are not reported distances from the air. However if tower says that the visual range from the tower is 2000, I can no longer shoot that app correct?)"

-You can legally shoot the approach under part 91 even if the visibility is zero (however, expect to go missed). Part 121 requires you to have minimum prescribed visibility for the approach prior to crossing the FAF. Under Part 91, weather only controls whether or not you can descend below minimums, and even then it's based on inflight visibility (what you see) and not what tower sees.


"1 more.... grid MORA. what area does it cover? like a 50 mile radius?"

-look at an enroute chart....you'll see square "grids" made up of intersecting lines of latitude and longitude. The MORA is valid within the entire grid (notice how there's only one MORA number for each grid?)

As for MOCA and MCA...you are 100% correct.

Hope this helps. Good luck on your instrument ride! Keep studying and asking questions, but don't get distracted by the 121 stuff....it can be a bitch to learn even after you have a solid understanding of part 91 regs!

[minitour]

Originally Posted by taseal

I'm going over some airline interviews to see if I can catch any IFR stuff that I might have missed (I think its a good way to find out some questions people ask) and I came across this. but I don't quite get it:

• Decode a METAR and TAF
  • Can we depart (referencing a 10-9 airport information page)?
  • How do you know?
  • What if RVR is reported as 6-6-6, can we depart?
  • What if it drops to 5-6-6?
  • What if an RVR value isn’t reported put the others are 6 and 6, can we depart? How do you know?
  • Convert Celsius to Fahrenheit
  • If visibility is ½ miles and RVR is 1200 can we depart?

If you're prepping for the Instrument Rating practical test (and I gather that you are) most of these things don't apply to you under part 91. Under air carrier regulations they become quite important if you want to stay legal but for now just learn what you need to stay legal and safe. From there, you'll want to make sure you establish some personal mins for after your checkride.

Please don't be stupid like I was and three days after your ride go blasting off by yourself in a piston single down to darn-near-minimums. If you do, two things will happen. 1. You'll scare the living ##### out of yourself. 2. You'll say "wow...I reeeeeeally shouldn't have done that" and you won't until you've gotten quite a bit of experience. That said, let's cover these questions. There's certainly no harm in extra knowledge.

whats with the 6-6-6, 5-6-6 and what isa 10-9 airport info page? something out of AIM? lol

The 6-6-6 or 5-6-6 are RVR values (600-600-600; Touchdown- Midfield - Rollout) from the three sensors and normally we just write them down and x100 to them. If I wrote 12-15-12 it would be 1200-1500-1200.

The 10-9 referenced is the airport diagram page under the jeppesen format. It has the takeoff minimums, any ODP, alternate minimums, landing distances, etc on it and you should reference it when you need to know "is there an ODP, what do I need to depart legally, where am I, etc." It's basically taking the info from the ODP section of the NOS book, the airport diagram, the LAHSO section, alternate minimums section, etc and put it on one page for each airport rather than making the pilot flip back and forth.

If you're using Jeppesen products (approach plates) for your rating, you really need to know this. If you're using NACO TPP books, then this is no big deal. It doesn't matter what you use so long as you know the product.

if there isa RVR reported, 121 guys need a certain RVR (or vis if no RVR present) to TO right? this doesn't apply to 91 however. we can depart 0 vis if we wanted.

Correct. That's why the questions of "can we depart if the RVR is X-Y-Z" exist. Under air carrier regulations you need certain visibility and/or RVR and that's usually defined in the op specs for that carrier. The interviewers or check airmen ask to make sure you understand the regs and/or op specs clearly.

I'm also a bit confused about the diff between RVV and RVR. what is the diff?

I've never heard a good answer to this, so I'll defer to someone more familiar.

lets say the RVR is 1800 and vis 1/4. the mins for that app is higher (3600 and 3/4 lets say) as a part 91 pilot, can I still shoot that app? (afaik I can still shoot the app as a part 91 pilot, because both are not reported distances from the air. However if tower says that the visual range from the tower is 2000, I can no longer shoot that app correct?)

Under part 91, you can fly any part 97 approach any time you want even if the weather is 0/0. The question becomes "can I land?" or maybe even "can I continue below DH/MDA?" and your answer lies in 91.175.

You'll need flight visibility (IOW; If the plate says 1/2, can you see 1/2 mile in front of you when you get down to the bottom? If yes....continue. If no, then you may not continue to the runway) not reported visibility or even RVR. Now, if you landed when the RVR was reporting 1800, pulled into the ramp and a FAA inspector asked how you got in...you may have a hard time saying "well I could see 3/4 mile in front of me at the bottom". Can either of you prove it? Not really. He gets to use 91.13 if he really wants to press the issue, so be careful.

I feel ready for this end of course, but I get nervous near the end and I start questioning myself. especially when they do the 'are you sure' trick. hopefully everything will go fine. I'll put up some questions as I think of them and can't figure it out.[/quote
Perfectly normal to get nervous getting ready for a checkride. I did 3 135 rides in a 5 week period and I was as nervous for each of those as I was for my ATP ride. I was as nervous for that as I was for my CFI rides. I was as nervous for that as I was for my private pilot ride. It happens.

The "are you sure?" trick is just there to make sure you're confident in your decisions. Just be confident. Also remember you won't be signed off unless your instructor knows you're ready. Be confident in your decisions and answers and I think you'll do fine.

...and no matter what anyone says, keep asking questions.

[quoteps: another one what is diff between MCA and MOCA.

MCA = min crossing alt (yo must be at this alt by the time you cross that fix, but what are the obst clearance altitudes?)

MOCA = min obst clearance alt which provides 1,000 non mts, 2,000 mts clearance, plus reliable nav aid reception upto 22 miles from the navaid)

They both keep you from hitting stuff, I'll assume (not a TERPS kinda guy) that they both provide 1,000' or 2,000' of obstacle clearance depending on whether or not you're in a mountainous area.

oh, 1 more.... grid MORA. what area does it cover? like a 50 mile radius? I know the MORA is 10NM from eachside of the airway. butnot sure about grid MORA. I know they turn red after 14,500 though.

That's a great question. I never really thought about how much area it covers. I just know that the number in the square covers that entire square and should provide you the same obstacle clearance discussed before.

As for what makes an area mountainous...I think it has to do with something like 3,000' of elevation change within 10 miles...something like that.

As was previously mentioned, check out the chart in the AIM and it outlines the "mountainous area" in the US. Really anything Denver and west and the eastern part of the US is pretty much "mountainous". Everything else is 'flatlander' country.

Good luck with the ride! Keep the good questions coming!

-mini

[MidlifeFlyer]

Originally Posted by taseal

I'm going over some airline interviews to see if I can catch any IFR stuff that I might have missed

Let me join the others who suggested that airline interview questions that are likely to look at requirements that apply specifically to Part 121 ops might not be the most appropriate study material for a private pilot instrument checkride.

No only are you not likely to be asked them, but the right answer under Part 121 may be the wrong answer under Part 91.

If you feel the need for additional study, take germb747's advice and get one of the study guides that is specific to the IR oral and will cover many of the questions you are actually likely to ask.

[taseal]

This is great guys, thanks!

I didn't know the 6-6-6 stuff was 121. Yeah, I won't touch any 121 stuff for now to confuse myself. at least I know what it is now though....

Chrisdahut1, I was told by my inst that since the tower is in the 'air' it counts as inflight visibitlity. thats why if they say the visibility from tower is xxx, thats it... altough I looked at inst procedures book, and it says I can shoot the app no matter what. doesn't say anything about tower, so I guess what my inst said was not valid.

Germb747, you say when I have app lights in sight, I can go 100feet below mins. I thougt when you see the app lights, you can go 100agl. not 100ft below mins? (if MDA is 580, I could go 480 you mean? I was always told to go 100 AGL)

oh, I have that guide btw. its good stuff....

[taseal]

Originally Posted by minitour

As for what makes an area mountainous...I think it has to do with something like 3,000' of elevation change within 10 miles...something like that.

As was previously mentioned, check out the chart in the AIM and it outlines the "mountainous area" in the US. Really anything Denver and west and the eastern part of the US is pretty much "mountainous". Everything else is 'flatlander' country.

Good luck with the ride! Keep the good questions coming!

-mini

yeah, thats what I wanted to know. I know the chart, just can't remember what defines it. its something like you said, if there is x amount of alt change within x miles, its mountainous.

Originally Posted by minitour

Please don't be stupid like I was and three days after your ride go blasting off by yourself in a piston single down to darn-near-minimums. If you do, two things will happen. 1. You'll scare the living ##### out of yourself. 2. You'll say "wow...I reeeeeeally shouldn't have done that" and you won't until you've gotten quite a bit of experience.

-mini

HAH! I live in FL. the worst I'll ever see is low vis for about 20 mins out of the whole day for a specific airport.

However, i feel very confident if I were to shoot an ILS down to mins. but thats my problem. I always feel over confident until t really happens. then I go, 'holy ####. not as easy as I thought' altough. how much worse can it be? I'm one of those guys that NEVER look out the window until I'm told to do so to get the full effect lol

[milski]

Originally Posted by taseal

Chrisdahut1, I was told by my inst that since the tower is in the 'air' it counts as inflight visibitlity. thats why if they say the visibility from tower is xxx, thats it... altough I looked at inst procedures book, and it says I can shoot the app no matter what. doesn't say anything about tower, so I guess what my inst said was not valid.

I disagree with him, you are the one that needs the required flight visibility from your position and it is not necessary the same as what tower has. If there's a fog bank right at the end of the runway, tower may be able to see the runway and report 10+ but if you're in the fog during the approach your flight visibility will be 0 or at least much less than 1/2 SM - I've had that happen to me.

Originally Posted by taseal

Germb747, you say when I have app lights in sight, I can go 100feet below mins. I thougt when you see the app lights, you can go 100agl. not 100ft below mins? (if MDA is 580, I could go 480 you mean? I was always told to go 100 AGL)

91.175.c.(3).(i) The approach light system, except that the pilot may not descend below 100 feet above the touchdown zone elevation using the approach lights as a reference unless the red terminating bars or the red side row bars are also distinctly visible and identifiable.

It's 100 ft above the TDZE. While with the typical minimum for an ILS being 200 ft, that's 100 ft below DH, it's not correct for approaches with different MDA/DH. I'm not sure how useful that rule is at all for non-precision approaches. If you're say 500 ft AGL and all you can see are the approach lights, it would seem to me that you're way too close to the runway, way too hight to make a normal landing, or if you're far enough than the visibility is good enough for you to see the runway before starting your descend. Someone with more experience might what to share it.

[taseal]

Originally Posted by milski

I disagree with him, you are the one that needs the required flight visibility from your position and it is not necessary the same as what tower has. If there's a fog bank right at the end of the runway, tower may be able to see the runway and report 10+ but if you're in the fog during the approach your flight visibility will be 0 or at least much less than 1/2 SM - I've had that happen to me.



91.175.c.(3).(i) The approach light system, except that the pilot may not descend below 100 feet above the touchdown zone elevation using the approach lights as a reference unless the red terminating bars or the red side row bars are also distinctly visible and identifiable.

It's 100 ft above the TDZE. While with the typical minimum for an ILS being 200 ft, that's 100 ft below DH, it's not correct for approaches with different MDA/DH. I'm not sure how useful that rule is at all for non-precision approaches. If you're say 500 ft AGL and all you can see are the approach lights, it would seem to me that you're way too close to the runway, way too hight to make a normal landing, or if you're far enough than the visibility is good enough for you to see the runway before starting your descend. Someone with more experience might what to share it.

ok, cool. 100 TDZE.

[Number1atNumber2]

Originally Posted by taseal

This is great guys, thanks!

I didn't know the 6-6-6 stuff was 121. Yeah, I won't touch any 121 stuff for now to confuse myself. at least I know what it is now though....
my inst said was not valid.

Germb747, you say when I have app lights in sight, I can go 100feet below mins. I thougt when you see the app lights, you can go 100agl. not 100ft below mins? (if MDA is 580, I could go 480 you mean? I was always told to go 100 AGL)

oh, I have that guide btw. its good stuff....

Edit: dough, someone beat me to what I was going to say.

[germb747]

yea, sorry about that. I'm used to thinking about a typical ILS with 200ft mins, but my verbage was incorrect. 100 feet above TDZE it is.

[tgrayson]

Originally Posted by taseal

its something like you said, if there is x amount of alt change within x miles, its mountainous.

I've never seen such a criterion, so I'm skeptical it exists. I think someone just drew boxes around sections of the US that looked bumpy and left it at that.

[FrankiegPilot]

Originally Posted by tgrayson

I've never seen such a criterion, so I'm skeptical it exists. I think someone just drew boxes around sections of the US that looked bumpy and left it at that.

That dammm Jeppesen !